Re: [HACKERS] PSQL commands: \quit_if, \quit_unless

David G. Johnston wrote:

> Being able to do more conditional work in psql would make setting up more
> robust scripts easier and without either losing transaction capabilities or
> session pooling for improved performance when large numbers of small
> commands are run in between flow control in done in bash.

Have you tried to script processes in shell using a single background
psql process with which the shell code communicates using a pipe?  I've
long been curious about that approach, but never had a strong need
enough to actually write the code.  It should be possible.